libblkid: add partial support for superblock binary API

The API is used only internally.

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/shlibs/blkid/src/superblocks/superblocks.c b/shlibs/blkid/src/superblocks/superblocks.c
index 9c71597e1d5b3ca51d143f9f89fe0fce9f1371b8..6ed0de6e6838b3f3b3e807722453569a9f5fc2a7 100644 (file)
--- a/shlibs/blkid/src/superblocks/superblocks.c
+++ b/shlibs/blkid/src/superblocks/superblocks.c
@@ -71,6 +71,7 @@
 
 static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn);
 static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn);
+static void superblocks_free(blkid_probe pr, void *data);
 
 static int blkid_probe_set_usage(blkid_probe pr, int usage);
 
@@ -154,9 +155,23 @@ const struct blkid_chaindrv superblocks_drv = {
        .nidinfos     = ARRAY_SIZE(idinfos),
        .has_fltr     = TRUE,
        .probe        = superblocks_probe,
-       .safeprobe    = superblocks_safeprobe
+       .safeprobe    = superblocks_safeprobe,
+       .free_data    = superblocks_free
 };
 
+/*
+ * Private chain data
+ *
+ * TODO: export this data by binary interface (see topology.c or partitions.c
+ *       for more details) by blkid_probe_get_superblock() or so.
+ */
+struct blkid_struct_superblock {
+       blkid_loff_t    magic_off;              /* offset of the magic string */
+       int             usage;
+};
+
+/* TODO: move to blkid.h */
+typedef struct blkid_struct_superblock *blkid_superblock;
 
 /**
  * blkid_probe_enable_superblocks:
@@ -296,6 +311,39 @@ int blkid_known_fstype(const char *fstype)
        return 0;
 }
 
+/* init and returns private data */
+static blkid_superblock superblocks_init_data(blkid_probe pr,
+                                       struct blkid_chain *chn)
+{
+       DBG(DEBUG_LOWPROBE, printf("initialize superblocks binary data\n"));
+
+       if (chn->data)
+               memset(chn->data, 0,
+                       sizeof(struct blkid_struct_superblock));
+       else {
+               chn->data = calloc(1,
+                               sizeof(struct blkid_struct_superblock));
+               if (!chn->data)
+                       return NULL;
+       }
+       return chn->data;
+}
+
+static void superblocks_free(blkid_probe pr, void *data)
+{
+       free(data);
+}
+
+static blkid_superblock superblocks_copy_data(blkid_superblock dest,
+                                               blkid_superblock src)
+{
+       if (!src || !dest)
+               return NULL;
+
+       memcpy(dest, src, sizeof(struct blkid_struct_superblock));
+       return dest;
+}
+
 /*
  * The blkid_do_probe() backend.
  */
@@ -317,6 +365,9 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
                 * is 1 byte */
                goto nothing;
 
+       if (chn->binary)
+               superblocks_init_data(pr, chn);
+
        i = chn->idx + 1;
 
        for ( ; i < ARRAY_SIZE(idinfos); i++) {
@@ -386,15 +437,11 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
                                (unsigned char *) id->name,
                                strlen(id->name) + 1);
 
-               if (chn->flags & BLKID_SUBLKS_USAGE)
-                       blkid_probe_set_usage(pr, id->usage);
+               blkid_probe_set_usage(pr, id->usage);
 
-               if (hasmag && (chn->flags & BLKID_SUBLKS_MAGIC)) {
-                       blkid_probe_set_value(pr, "SBMAGIC",
-                               (unsigned char *) mag->magic, mag->len);
-                       blkid_probe_sprintf_value(pr, "SBMAGIC_OFFSET",
-                               "%llu", off);
-               }
+               if (hasmag)
+                       blkid_probe_set_magic(pr, off, mag->len,
+                                       (unsigned char *) mag->magic);
 
                DBG(DEBUG_LOWPROBE,
                        printf("<-- leaving probing loop (type=%s) [SUBLKS idx=%d]\n",
@@ -423,6 +470,9 @@ nothing:
  */
 static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn)
 {
+       blkid_superblock sb = NULL;
+       struct blkid_struct_superblock sb_buff;
+
        struct blkid_prval vals[BLKID_NVALS_SUBLKS];
        int nvals = BLKID_NVALS_SUBLKS;
        int idx = -1;
@@ -440,6 +490,8 @@ static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn)
                        /* save the first result */
                        nvals = blkid_probe_chain_copy_vals(pr, chn, vals, nvals);
                        idx = chn->idx;
+                       if (chn->data)
+                               sb = superblocks_copy_data(&sb_buff, chn->data);
                }
                count++;
 
@@ -463,11 +515,33 @@ static int superblocks_safeprobe(blkid_probe pr, struct blkid_chain *chn)
        /* restore the first result */
        blkid_probe_chain_reset_vals(pr, chn);
        blkid_probe_append_vals(pr, vals, nvals);
+       if (sb && chn->data)
+               superblocks_copy_data(chn->data, sb);
        chn->idx = idx;
 
        return 0;
 }
 
+int blkid_probe_set_magic(blkid_probe pr, blkid_loff_t offset,
+                       size_t len, unsigned char *magic)
+{
+       int rc = 0;
+       struct blkid_chain *chn = blkid_probe_get_chain(pr);
+
+       if (chn->flags & BLKID_SUBLKS_MAGIC) {
+               if (magic && len)
+                       rc = blkid_probe_set_value(pr, "SBMAGIC", magic, len);
+               if (!rc && offset)
+                       rc = blkid_probe_sprintf_value(pr, "SBMAGIC_OFFSET",
+                                       "%llu", offset);
+       }
+       if (!rc && chn->data) {
+               blkid_superblock sb = (blkid_superblock) chn->data;
+               sb->magic_off = offset;
+       }
+       return rc;
+}
+
 int blkid_probe_set_version(blkid_probe pr, const char *version)
 {
        struct blkid_chain *chn = blkid_probe_get_chain(pr);
@@ -495,8 +569,17 @@ int blkid_probe_sprintf_version(blkid_probe pr, const char *fmt, ...)
 
 static int blkid_probe_set_usage(blkid_probe pr, int usage)
 {
+       struct blkid_chain *chn = blkid_probe_get_chain(pr);
        char *u = NULL;
 
+       if (chn->data) {
+               blkid_superblock sb = (blkid_superblock) chn->data;
+               sb->usage = usage;
+       }
+
+       if (!(chn->flags & BLKID_SUBLKS_USAGE))
+               return 0;
+
        if (usage & BLKID_USAGE_FILESYSTEM)
                u = "filesystem";
        else if (usage & BLKID_USAGE_RAID)

diff --git a/shlibs/blkid/src/superblocks/superblocks.h b/shlibs/blkid/src/superblocks/superblocks.h
index 12f197e590069815731aaa6c110ab6ee0d21c7ce..b1fa49d502461f73b31f5a1c934f06c98131bfa4 100644 (file)
--- a/shlibs/blkid/src/superblocks/superblocks.h
+++ b/shlibs/blkid/src/superblocks/superblocks.h
@@ -69,6 +69,8 @@ extern const struct blkid_idinfo befs_idinfo;
 /*
  * superblock functions
  */
+extern int blkid_probe_set_magic(blkid_probe pr, blkid_loff_t offset,
+               size_t len, unsigned char *magic);
 extern int blkid_probe_set_version(blkid_probe pr, const char *version);
 extern int blkid_probe_sprintf_version(blkid_probe pr, const char *fmt, ...)
                __attribute__ ((format (printf, 2, 3)));